Escher and the Droste effect

Step 1: unraveling Escher's picture

The first phase of the project was to reconstruct the straightened
Malta landscape from Escher's picture by using Escher's grid.
Joost Batenburg produced these pictures with a computer program
from the scanned picture and the grid of Escher.

The resulting Droste picture is preserved under scaling by a
factor 256=28. You can view this picture as
a cycle of 8 frames,
each time zooming in by a factor of 2.